It's nitrided. That helps. Faster lobes need higher spring rates. They die just as quick from spring pressures too low. I've run 180 on the seat with a SFT. It lasted over 150 runs and that's a lot of spring pressure for SFT's
Seat pressure doesn't mean much-its spring rate and open pressure that should be considered first. What if you had a spring that had 200 seat and 300 open? Would it kill a lobe? J.Rob